How can i put a Force Field between two items for Keyed particles?
With the physics set to newtonian, boids or fluid, particles are influenced by force fields and curve guides, while keyed particles only follow their own control systems. Keyed particle systems move particles from the position of one system to the position of another particle system. The key point is that you can use more than two systems for keyed particles.

By having a third system in the middle that uses newtonian physics I got the keyed particles to follow the middle particles as they followed the curve.